A technique for providing, in a processor of a processor system, a trace condition detection signal output terminal that can detect, from the outside, a trace condition detection signal is known. With this technique, a peripheral circuit can take in a trace condition detection signal via the trace condition detection signal output terminal. As a result, the peripheral circuit can perform state information tracing in association with program tracing performed by the processor. Therefore, detailed software debugging can be easily performed on the processor system including the processor and the peripheral circuit.
Also, a technique for connecting, via a connection line, a personal computer (PC) card that is a target device to be debugged to a host device that is a debugging device and performing debugging is known. With this technique, the target device executes a debugging program. Also, the target device sends output information of the debugging program to the host device, waits for a command from the host device, and, if a command is sent, performs processing specified by the command. Also, the host device outputs, to a display unit, POD_ID executed by the target device, line number, source file, comment, and the like.